About the Study

Frequently Asked Questions

About the Ontario Health Study

What sets the Ontario Health Study apart from other studies is its potential to reach a large and diverse population residing in Ontario. With it being possible to follow the health of so many diverse people, the Study may detect new risk factors or combinations of risk factors and may be able to investigate many less common diseases. The ethnic and geographic diversity in Ontario also makes the province ideal for an investigation into a variety of risk factors for common diseases across different ethnic groups and environments. The OHS is one of the first studies to collect data relevant to many diseases from a large-enough number of people to draw meaningful conclusions. The Ontario Health Study is part of the Canadian Partnership for Tomorrow’s Health, a landmark study whose goal is to recruit and follow the health of 300,000 Canadians in five regions across the country.

Also making the Ontario Health Study unique is that it takes advantage of the many research resources existing in Ontario, including world-leading medical research in many areas. For example, when you give us your permission to link to your administrative data, we are able to link to many valuable sources of information that are unique to Ontario, such as the Ontario Cancer Registry. Some of the best-linked health data in the world – collected for routine administrative purposes – exists in Ontario.

Diseases such as cancer, heart disease and diabetes are the primary causes of death in Canadian adults and treating these and other illnesses costs the Canadian health care system billions of dollars annually. Additionally, we are starting to see the onset of diseases in younger populations. The Ontario Health Study will try to discover which factors increase the risk of developing various diseases, as well as what can be done to reduce the chance of developing them. These risk factors may include where people live and work, what they eat, how much they exercise, whether they smoke and other factors that have not yet been identified.

Findings from other long-term studies have already helped improve health care for all of us. This is your chance to help make a difference to the health of future generations. Also, by participating in the Ontario Health Study, you will be part of a broader, pan-Canadian initiative as the OHS is part of the Canadian Partnership for Tomorrow’s Health (CanPath). To learn more, visit canpath.ca.

Though our primary method of staying in touch with you will be through email, we may also contact you via regular mail or phone. As technology changes over time, we may use additional ways to contact you as well.

The OHS is funded by four agencies and government partners whose goals include conducting research to improve care and reduce the number of people who are diagnosed with common diseases. The goal of the Ontario Health Study is to investigate what causes diseases and to improve strategies for the prevention and treatment of these diseases.

No. The Ontario Health Study is a not-for-profit health research platform begun in 2009, when the OHS began to recruit more than 225,000 Ontario adults to complete health-related online questionnaires to follow their health over time. The OHS is part of the Ontario Institute for Cancer Research located in Toronto.

Taking Part

The Ontario Health Study will continue for a long time, and one of the goals of the Study is to collect information about your health throughout your lifespan. You will be contacted again in the future to complete additional questionnaires, and may be asked to provide additional samples and measurements. Each time you are invited to participate in a new part of the Ontario Health Study, you will receive a series of reminders to complete that activity. These reminders will provide you with an opportunity to learn more about what you are being asked to take part in, and to ask any questions you might have. The Study will also send you updates about the progress the Ontario Health Study is making, and information about new initiatives the Study is planning. You can always choose not to receive these updates, and providing additional information, measurements or samples to the Study is voluntary.

As the COVID-19 pandemic continues to affect our lives worldwide, we seek your help to better understand and track the impact of the virus. We want to assess the impact that COVID-19 has had on your physical and mental health, employment, and to identify your risk factors. Your de-identified information will be added to the OHS data already collected through previous questionnaires.

The same COVID-19 Questionnaire is being administered by other regional cohorts from the Canadian Partnership for Tomorrow’s Health (CanPath). We are also collaborating internationally to learn more about pandemic experiences here in Ontario, as well as the U.S., and Europe. The information you choose to provide will be of great help to Canadian and international researchers, and will enrich the OHS health research platform.

Yes! We know this pandemic has impacted Canadians in many ways, including economically, psychologically, and socially. The information you choose to provide will be of great help to Canadian and international researchers, and will enrich the OHS health research platform.

The COVID-19 questionnaire ask about both our participants’ physical and mental health. Because a person’s state of mind can greatly affect their health, and vice versa, researchers will be very interested to understand how participants are faring during this pandemic, and how their health may have changed over time.

Should you be experiencing stress or anxiety and would like support, you can access a number of mental health services compiled by the Government of Ontario that are available online or by phone.

You may be self-isolating at home, but completing this questionnaire is a tangible, and incredibly valuable way you as an OHS participant can directly contribute to the global scientific efforts currently underway.

Your answers to questions about your COVID-19 symptoms (or lack of them), any treatment, and your current health status, will directly contribute to the Canadian and international body of research being developed to help us all understand how we come to be at risk for the virus, treatment approaches, and how our communities can work to lessen transmission. The data you provide will help researchers and public health leaders to understand how to best respond to the current COVID-19 pandemic as it evolves, and will also inform future pandemic responses.

The OHS is a ‘prospective cohort’ study, meaning participants, both healthy and with those with pre-existing conditions, are followed over time. Studies like the OHS can be critical when researchers want to estimate the true burden of infection and disease in a population.

Because of participants’ past contributions, the OHS is a ready-made, active research platform for researchers wishing to study the effects of the pandemic. To recreate this 10-year old cohort of 225,000 participants today from scratch would simply take too long and cost too much.

In the context of COVID-19, and in the absence of population-wide testing for the virus, population studies like the OHS provide an important opportunity to assess population-level prevalence, and identify the biological and lifestyle factors that make some people more likely to get the virus or make some get sicker from it than others. It can also help us to capture how our health may change over time as a result of COVID-19.

As a Study participant, you will be contacted again in the future to complete additional questionnaires, and may be asked to provide additional samples and measurements. The Ontario Health Study will continue for a long time, and one of the goals of the Study is to collect information about your health throughout your lifespan.

Some of the topics we expect to cover in follow-up questionnaires include mental health, diet and physical activity, stress levels, information about your work environment and lifestyle, and the walkability of your neighbourhood.

Once you have consented to participation in the Ontario Health Study, the information that you have provided will be retained unless you withdraw from the Study. Researchers may still find the information you did provide useful for their work.

If you are unable to recover your username using the “Forgot your username?” button on the log-in page, please contact the OHS at 1-866-606-0686 or info@ontariohealthstudy.ca for assistance. Our call centre is open Monday to Friday from 9 a.m. to 5 p.m.

If you experience technical difficulties while completing a questionnaire, please contact our call centre at 1-866-606-0686 or send an email to info@OntarioHealthStudy.ca. Our call centre is open Monday to Friday from 9 a.m. to 5 p.m.

You spend a lot of time at work and work has a big impact on you, whether it affects you mentally, physically or emotionally. Your job is relevant to your health and helps researchers make connections on how it impacts your health. The information from the Work History Questionnaire will be added to the data we’ve already collected through previous questionnaires regarding your health & lifestyle. This will create an even richer resource for research into the causes of cancer and other chronic diseases.

We contact our participants every couple of years to obtain updated health and lifestyle information using follow-up questionnaires, which are designed to be snapshots of participants’ health over a long period of time. If you gave us your permission to link to your administrative health data, changes will also be captured via administrative and medical databases such as OHIP and the Ontario Cancer Registry.

Privacy & Confidentiality

The security and confidentiality of your personal health information is very important to us. We have put in place strict security measures, which include sophisticated computer controls and highly secure access systems. The main methods we use to protect your confidentiality are:

1. Your information is stored with all identifying information removed (“de-identified”) – this means any information that can identify you, such as your name and address, date of birth or Health card number is removed from your data and stored separately.

2. All Information is password-protected and encrypted. In order to contact you and to link to your administrative and medical records, we need to be able to identify your information. We do this using a code. Only a limited number of Ontario Health Study staff with access to the code will be able to connect you with any of your information.

3. Access is kept to a minimum. Only a small number of staff members who have signed confidentiality agreements have access to the key code and they only access it for necessary operational purposes. The computers that hold your information are protected by the same kind of encryption technology that is used by banks to protect their customers’ online banking transactions.

All the information you provide is encrypted to ensure that your data remains confidential. This protection exists at all points between your web browser and the database files where your data is stored. Furthermore, identifiable information such as your name is placed in an isolated database separate from your questionnaire responses. At regularly scheduled intervals, your de-identified questionnaire responses are exported to another database for research and reporting purposes. All physical systems are hosted at a secure data centre in the Ontario Institute for Cancer Research. Due to the importance of the information collected by the OHS, we make back-up copies of the information in our databases on a regular basis. Certain third-party organizations have been hired by the OHS to store these copies or transport Study information, but this information is encrypted and they cannot see or use it.

Ontario Health Study/Ontario Institute for Cancer Research (OICR) staff: A limited number of staff members from the Ontario Health Study and the OICR IT department will have access to your personal information.

Researchers: The Ontario Health Study expects to receive requests from researchers in Canada and other countries to access the Study’s data. All requests must pass a strict scientific and ethical review and receive approval before any data will be shared with a researcher. The data collected from you will only be disclosed to researchers once all information that directly identifies you has been removed. Researchers who are given access to the Ontario Health Study must sign a Data Access Agreement to ensure that no attempt is made to re-identify participants.

Researchers who have received approval for a research study may wish to collect information from you that has not been collected as part of the Ontario Health Study. If this occurs, you will be contacted by the Ontario Health Study regarding the request. You have the option to participate in the research study or to refuse. A list of approved studies will be maintained on the OHS website for your information.

Research Ethics Board: The Research Ethics Board has the right to review Study data in order to ensure that the Ontario Health Study is following proper procedures.

You do not have to provide your Health card number in order to participate in the Ontario Health Study. However, we ask you to give it to us so we can link the information you provide to the OHS to your routinely collected administrative/medical data and your health records. For example, every time you undergo certain tests (e.g., a mammogram), the fact that you had this test is noted and stored in a database. This is referred to as “administrative data.” By linking the information you provide to the OHS with administrative data, researchers are able to ask a broader range of questions, such as whether screening programs are effective and whether there are “hot spots” across the province where a certain disease is more common. Since data linkage involves linking information about the same person from multiple sources, it is important to make sure that the information being linked is about the same person. Your Health card number is unique to you and is the perfect means to link information. Very strict privacy practices are in place when information from multiple sources is linked together. Researchers must document how they will ensure the confidentiality of your information and must receive approval from a Research Ethics Board before they can access your health information.

The Ontario Health Study was granted approval by the Research Ethics Board at the University of Toronto. This approval must be renewed on a yearly basis through a renewal application that is submitted by the OHS. The Research Ethics Board approves all aspects of the research study and ensures that it meets the required ethical criteria. The Ontario Health Study also receives oversight from an independent Ethics Advisory Committee, which includes members who are experts in bioethics and privacy.

International researchers must receive ethical approval from the organizations they work for prior to obtaining any Ontario Health Study data. All proposals will be reviewed by the Study’s Data Access Committee and researchers must sign a Data Access Agreement before they are given access to Ontario Health Study data.

Results of the research that is conducted with OHS data may provide information that will enable drug companies and other industry groups to develop new therapies and improve existing therapies. For example, drug companies rely heavily on research data from studies such as the Ontario Health Study for the development of new drugs and they play an important role in translating research data into tangible outcomes.

The Ontario Health Study may collaborate with industry groups within strict guidelines and only with approval from the Ontario Health Study Ethics Advisory and Scientific Advisory committees. The only health data that the OHS will ever give to a commercial enterprise will be information culled from a number of users – individual-level health data will not be given out. Study researchers will analyze the data ‘in-house,’ and industry groups will be provided only with the summarized results of this analysis. That is, results provided to industry will be at the population level, not at the individual level.

Industry collaborators will be obliged to pay a fee for the data they receive and are required to share their research findings with the Ontario Health Study. Any funds generated through industry collaboration will be used to support health-related research, educational and community programs in the province of Ontario, and to cover the costs of maintaining Ontario Health Study resources.

Your information is being collected for research purposes, and will not be accessible to the police, law enforcement officials or lawyers unless there is a requirement to do so by law (e.g., in very rare situations, a warrant could be issued by a court of law). This is largely hypothetical as we are not aware of any instance of the courts requesting information collected for health research purposes. If we were ever required to provide authorities with your information, we would inform you of the legal investigation if possible.

Consent & Withdrawal

The success of the Ontario Health Study is dependent upon the ability to follow participants over many years. The value of your information will be greatly reduced if you withdraw from the Ontario Health Study. However, you are able to withdraw from the Study at any time. If you decide you no longer want to participate, we will not contact you for any additional information. To withdraw from the Study, please log in to your OHS personal home page and click on “Study Preferences” in the blue banner. Next click the “Withdrawal Options” box. You will be asked to indicate what you would like the OHS to do with the information you have already provided to the Study. You can choose from one of the following three options:

No further contact: the Ontario Health Study will no longer contact you or ask you to participate in ongoing Study activities, but will continue to have your permission to keep and use information and samples you have already provided, and to continue to access information in administrative or medical databases (e.g., the Ontario Cancer Registry) and your personal medical records if you consented to this at the time you enrolled.

No further access: the Ontario Health Study will no longer contact you or ask you to participate in ongoing Study activities, and will not collect any further information about you from administrative and medical databases (e.g., the Ontario Cancer Registry) or your personal medical records, but will still have permission to keep and use information and samples you have already provided.

No further use: the Ontario Health Study will no longer contact you or ask you to participate in ongoing Study activities, collect additional information about you, and any information or samples you have already provided will be removed from our databases. It is not possible to remove information or samples that have already been provided to researchers for analyses. Your signed consent and withdrawal will be kept as a record of your wishes.

Should you have any questions or if you would like more information about your withdrawal options, please telephone the call centre at 1-866-606-0686, Monday to Friday, from 9 a.m. to 5 p.m., or send an email to info@ontariohealthstudy.ca.

Your consent will remain valid unless you withdraw from the Study. The information and samples you provide will be kept until they are no longer required for the purpose for which they were collected. Should this occur, a decision will be made about what to do with your information and any remaining samples.

Yes. An integral part of the Ontario Health Study as a research platform is ongoing follow-up, the collection of biospecimens, and linkage to administrative and personal health records. Participation in the Ontario Health Study is completely voluntary and you are free to withdraw from the Study at any time by calling 1-866-606-0686 or by writing to info@OntarioHealthStudy.ca.

Technical Issues

As a security precaution, our website will lock your account for one hour if the incorrect username and/or password are submitted three times in a row. To regain access we recommend resetting your password, which will immediately unlock the account and allow you to log in. Password reset instructions are available here. If the problem persists, please contact the Ontario Health Study call centre at 1-866-606-0686, Monday to Friday from 9 a.m. to 5 p.m. for assistance.

It is possible that you have missed answering a question on the page or entered an unacceptable value for a question. Please make sure you have not entered any extra spaces in open text fields as this is a common source of error messages. Please scroll to the top of the screen to check for any error messages that may appear. Error messages will appear just above the question that has caused the error.

The system will save all of the questionnaire answers you have provided up to this point (up to the last completed page). Please log in again to resume answering the questionnaire where you left off. If you cannot log in again, please contact our call centre at 1-866-606-0686 or send us an email at info@OntarioHealthStudy.ca for further assistance. Our call centre is open Monday to Friday from 9 a.m. to 5 p.m.

The speed at which the questionnaire moves from screen to screen could be affected by a few things, including the number of people online at the same time, the speed of your internet connection or the speed and configuration of your computer. To help improve the speed of the questionnaire, please close all other programs on your computer and do not download other files, programs or updates while you are completing the questionnaire. If the problem persists and you are not able to complete the questionnaire, please contact our call centre at 1-866-606-0686 or send us an email at info@OntarioHealthStudy.ca for further assistance. Please note that our call centre will not be able to diagnose or fix any technical issues with your actual computer. Our call centre can only answer questions related to the Study and is not an IT Help Desk. Our call centre is open Monday to Friday from 9 a.m. to 5 p.m.

The system will save all of the questionnaire answers you have provided up to this point (up to the last completed page). You may exit the questionnaire and log in again to resume where you left off. If you cannot log in to the questionnaire again, please contact our call centre at 1-866-606-0686 or send us an email at info@OntarioHealthStudy.ca for further assistance. Our call centre is open Monday to Friday from 9 a.m. to 5 p.m.

Please double check the response you are trying to enter. The questionnaire has been designed to allow responses that fit within certain categories. For many responses, this means that values entered have to be between certain ranges and values that are outside these ranges will create an error. For example, you cannot enter that you were diagnosed with a certain condition at age 65 when you are only 30. By designing the questionnaire in this way, we can ensure we are getting the most accurate data. If you continue to experience difficulty, please contact our call centre at 1-866-606-0686 or send us an email at info@OntarioHealthStudy.ca. Our call centre is open Monday to Friday from 9 a.m. to 5 p.m.

You may have made an error when typing your new password, OR your Caps Lock may be on

You may have entered an incorrect username

If you use a password manager tool, your computer may only have saved your old password. If this is the case, please delete the saved password and manually re-enter the new password in the password field.